1. Field of the Invention
The present invention is related to a driving circuit for pixels of an active matrix organic light-emitting diode display and a method for driving pixels of an active matrix organic light-emitting diode display, and particularly to a driving circuit for pixels of an active matrix organic light-emitting diode display and a method for driving pixels of an active matrix organic light-emitting diode display that are independent of process variation of a thin film transistor and voltage drop of an organic light-emitting diode.
2. Description of the Prior Art
A metal line of a common low-voltage terminal of a driving circuit for pixels of an active matrix organic light-emitting diode (AMOLED) display has an impedance, therefore voltages of source terminals of N-type thin film transistors for driving different organic light-emitting diodes may be different from each other, which would cause driving currents flowing through the different organic light-emitting diodes to be different from each other. Luminance of the organic light-emitting diode is controlled by the driving current, so the different driving currents cause uneven luminance of a panel.
Further, due to process variation during fabrication of the thin film transistor, threshold voltages (VTH) of the thin film transistors driving the organic light-emitting diodes may be equal or unequal. Therefore, even if the thin film transistors are given the same data voltage, the driving current generated by the thin film transistors may still be unequal, resulting in the uneven luminance of the panel. In addition, after utilizing the organic light-emitting diode for a period of time, a voltage drop of the organic light-emitting diode is increased due to degradation of the organic light-emitting diode. Because the voltage drop of the organic light-emitting diode is increased, luminance of the organic light-emitting diode given the original data voltage is decreased, resulting in image sticking of the panel.